Russia has moved heavy military equipment towards its border with North Korea amid fears of a military clash between Pyongyang and the United States.

A flurry of military activity in Russia's far east came as the UN Security Council condemned North Korea's latest missile test and threatened to impose new sanctions against Pyongyang for its "highly destabilising behaviour".

In a unanimous statement, the council demanded that North Korea "conduct no further nuclear tests" and said Pyongyang's "illegal missile activities" were "greatly increasing tension in the region and beyond".

North Korea carried out a failed missile test on Sunday, a day after displaying missiles at a parade in Pyongyang.

The Rodong Sinmun, the official newspaper of the North's ruling Workers' Party, said yesterday: "In the case of our super-mighty preemptive strike being launched, it will completely and immediately wipe out not only US imperialists' invasion forces in South Korea and its surrounding areas but the US mainland and reduce them to ashes."

The threat appeared to be a response to comments by Rex Tillerson, the US secretary of state, who said the US was looking for ways to "bring pressure" on the North Korean regime into giving up its nuclear ambitions.

It was revealed earlier this week that a US aircraft carrier group led by the USS Carl Vinson would spend another 30 days at sea before heading towards North Korean waters.

Last week Donald Trump, the US president, said he had ordered an "armada"

into the northwest Pacific in a show of force designed to deter North Korea from further missile and nuclear weapons test.

The US defence ministry laster acknowledged the ships had actually travelled into the Indian Ocean to carry out manoeuvres with Australian forces, and only began their journey north recently.

Mr Trump has called on China, Pyongyang's only ally, to rein in North Korean leader Kim Jong-un, but has threatened to act alone to "solve" the problem if necessary.

Residents and local media in Russia's far east reported large military convoys travelling in the direction of the North Korean border since the weekend, in what appear to be contingency plans to contain fallout from a possible military clash between the United States and North Korea.

A video published by a local news site showed a train carrying 12 tracked vehicles, including Tor surface-to-air missile systems, towards Vladivostok.

Missiles

Reclusive North Korea regularly threatens to destroy Japan, South Korea and the US and has shown no let-up in its belligerence after Sunday's failed missile test.

Meanwhile, Mr Trump has been accused of "shocking ignorance" after asserting that Korea "used to be a part of China" shortly after a meeting with Xi Jinping, the Chinese president.

And the White House yesterday raised the possibility of Donald Trump meeting Pope Francis during the US president's trip to Italy in late May, although it stressed nothing has been scheduled.

"We will be reaching out to the Vatican to see if an audience with the pope can be accommodated," White House spokesman Sean Spicer said.